Construction of frozen walls for shafts in mines.



PATENTED AUG. 30, 1904.

I K. SCHMIDT. CONSTRUCTION OF FROZEN WALLS FOR SHAFTS IN MINESAPPLICATION FILED DEC. 19, 1903.

N0 MODEL.

. llllpkIil IlNirEn STATES Patented August 30, 1904.

Parnr Caries.

KARL SCHMIDT, OF ERKELFNZ, GERMANY.

SPECIFICATION forming part of Letters Patent No. 768,774, dated August30, 1904. I

Application filed December 19, 1903. Serial No. 185,789. (No model.)

To all whom, it may concern.-

Be it known that I, KARL ScI-IMIDT, a citizen of Germany, residing atErkelenz, Rhineland, Germany, have invented certain new and usefulImprovements in the Construction of Frozen lValls for Shafts in Mines,of which the following is a specification.

This invention relates to a process of forming frozen walls for shaftsin such a manner that the freezing liquid is thoroughlyutilized and anequal freezing temperature is obtained within the freezing-tubes. Inthis way a reliable and uniformly-frozen wall is formed, under theprotection of which the shaft may be sunk.

In the accompanying drawings, Figure 1 is a sectional elevation of anapparatus for carrying my invention into effect; Fig. 2, a similar viewof a modification, and Fig. 3 a plan of a shaft constructed according tomy invention.

In practicing my invention I sink a series of vertical conduits in acircle around the shaft to be constructed. Each conduit is composed ofan outer pipe (6 and an inner pipe 7), the pipes communicating with eachother near the bottom of the conduit. At its upper end the pipe (4 ofone conduit is connected by a branch to the pipe Z; of a second conduit.The pipe (4 of this second conduit is connected to a pipe I) of a thirdconduit, &c.

The freezing medium*such as liquid carbonic acid, ammonia, sulfurousacid, &c.is c nveyed from a compressor (not shown) to the mouth of oneof the pipes I). The freezing medium will descend within this pipe andenter pipe (0 at the bottom of the conduit. Thence it passes upwardlythrough pipe (4 to the pipe 6 of the second conduit, and so on throughthe series.

In order to form a uniform frozen wall, I arrange the conduits in aplurality of overlapping groups. l/Vith the construction shown in Fig. 3the pipe at of the first conduit is coupled to the pipe 6 of the fifthconduit, while the pipe (I of such fifth conduit is coupled to the pipe7/ of the ninth conduit, &c. In like manner the second, sixth, tenth,&c., conduits are connected and the third, seventh, eleventh,

&c., conduits, &c. The freezing medium circulating through the abovegroups of conmunicating tubes will progressively expand as it absorbsheat. The vapors which are formed during this process will escape fromthe last tube of each group to be reconveyed to the compressor. By thearrangement described the freezing efiect of one group of conduits willbe reinforced by that of another overlapping group, so that soft orunfrozen zones or spaces are avoided. Furthermore, the freezing mediumwill flow more regularly through the series of connected pipes than itwould through a large number of single pipes, as was heretoforepracticed.

It is of advantage that all the tubes, as Well as the couplings, have auniform diameter. This insures that the wet Vapors, which graduallyexpand, as above stated, will flow through the pipes with aconstantly-increasing velocity, whereby a uniform transmission of coldthrough the Walls of the pipes is obtained.

In Fig. 2 the conduits are composed of two pipes a and b, which arearranged side by side andcommunicate with each other at the bottom by anelbow. The freezing medium is conveyed to the first pipe 6 of one group,whence it passes through pipe at to the pipe 6 of a second conduit, asalready described.

WVhat I claim is a 1. Improved means for forming frozen walls for shaftsembracing a plurality of groups of connected freezing-tubes, and afreezing medium conveyed through said groups, substantially asspecified.

2. Improved means for forming frozen walls for shafts embracing aplurality of overlapping groups, I each composed of connectedfreezing-tubes, and a freezing medium conveyed through said groups,substantially as specified.

In Witness whereof I have hereunto subscribed my name in the presence oftwo witnessess.

KARL SCHMIDT.

- l/Vitnesses:

WILLIAM EssENwnIN, PETER LIEBER.

